Conducting linkage for a tilting insulator switch



J. B. OWENS Dec. 24, 1957 CONDUCTING LINKAGE FOR A TILTING INSULATOR SWITCH Filed Aug. 16, 1955 INVENTOR. JAMES 8.0146936 BY MM M Mfi 477ae/V '75 United States Patent CONDUCTING LINKAGE FOR A. TILTING INSULATOR SWITCH James B. Owens, Greensburg, Pa., assignor to l-T-E Circuit Breaker Company, Philadelphia, Pa., a corporation of Pennsylvania Application August 16, 1955, Serial No. 528,668

1 Claim. (Cl. 200-48) My invention relates to tilting insulator switches and.

more particularly to a tilting insulator switch having a conducting linkage for fastening the movable contact structure to a terminal, the conducting links being electrically and mechanically connected by an economical and effective contact structure.

Tiltinginsulator switches are outdoor air switches for electrical distribution circuits. The switches are so named because the movable. contact is actuated by the tilting motion of aninsulator to which it is fastened, this insulator being pivotally connected to the switch base. In the contact engaged position, the insulator is moved to one side of a vertical line through the pivot and is thereafter maintained in the engaged position by the force of gravity. Similarly, the insulator carrying the movable contact is moved to the other side of a vertical line through the pivot to place the contacts in their disengaged position, this position being maintained by the force of gravity. Although these switches do not provide the contact wiping and ice breaking motion that is provided in rotating insulator types of vertical break switches, they are extremely popular because of their simplicity and low cost.

In switches of this type, a flexible connection must be made between the movable contact assembly and a stationary terminal. This connection must be flexible since the distance between the stationary terminaland the movable contact structure is changed upon. motion of the movable contact into and out of engagement withastationary-contact which may contain the second terminal.

In the past, this flexible connection has been formed of either fine-wire braided shunts, finely-stranded copper cable, or a plurality of thin copper laminations. However, the flexible conductors of the type described above have very limited life, particularly in the corrosive atmospheres found near power plants or in industrial areas. Furthermore, the flexible connection per se is undesirable since there is always a danger of the flexible connector coming into contact with other structural members. in the vicinity of the switch, thereby creating dangerous electrical conditions.

The problem of a flexible connection being free to move in random directions has been so severethat in some cases, as is shown in U. S. Patent 1,963,418 to Pittman et al., a mechanical linkage is provided between the movable contact and the. terminal for the solefunction of supporting the flexible connection.

The principle of my invention is. to. provide. a conducting linkage for a tilting insulator switch, this linkage replacing the previously used flexibler connecting means for connecting the movable contact assembly to a. stationary terminal. This conducting linkage preferably consists of heavy solid copper bars which are held in high pressure, electrical contact engagement with the blade member and the terminal member. Clearly, in the application of my novel invention the conducting linkage, being a heavy solid copper bar, will enjoy long life even 2,817,726 Patented Dec. 24, 195.7

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in corrosion atmospheres. Similarly, my novel conducting linkage can provide required flexibility to allow a change in the distance between the movable contact structure and the stationary terminal and yet is rigid enough to overcome the possibility of an accidental short circuit by having the flexible conductor come into contact with other stationary structures in the vicinity of the switch.

Accordingly the primary object of my invention is to provide a conducting linkage for connecting the movable contact structure to a stationary terminal of a tilting insulator switch.

Another object of my invention is to provide an electrical connection between the movable contact structure and a stationary terminal of a tilting insulator switch, wherein the electrical connection is suitablexfor operating in corroding atmosphere of industrial areas and .is rigid enough to prevent accidental short circuiting of nearby structural members.

Another object of my invention. is to provide a conductive linkage for a tilting insulator switch, whereby the conducting links are held in high pressure electrical contact engagement. with the blade member and the terminal member.

A still. further object of my invention. is to provide a conducting linkage for connecting the movable contact structure of a tilting insulator switch to a stationary terminal, this conducting linkage being. simple to manufacture, and inexpensive.

Another object of my invention is to provide a connecting linkage for tilting insulator switches which comprises relatively rigid current carrying members, the distance betweenthe ends of the members fastened at the terminal and at the movable contact structure being free to change.

These and other objects of my invention will. become apparent from the following. description taken in con junction with the drawings in which:

Figure 1 shows a tiltinginsulator switch in which the movable contact assembly is connected to a stationary terminal by meansof the conducting linkage of my invention,.the movable contacts being in the engaged position.

Figure Zshows an end View of Figure l, as seen from.

the right hand side.

Figure 3 shows the switch of Figure l whenthe movable contact is in its disengaged position.

Figure 4 shows a top view of a portion. of the connectinglinkages of my novel invention including the link:

contact.

Figure 5 shows a detail drawing of a; link contact. Referring now to Figures 1, 2 and 3, a single pole tilting insulator switch constructed in accordance with my invention isshown in the. engaged position in Figure. 1, the disengaged position in Figure 3, and Figure 2.

shows an end view of the switch in the engaged position of Figure 1. As shown in these figures, a first insulator ltl-and a second insulator ll are attached in any desired:

manner as by the bolts Hand 13 to abase 1.4.. The insulator 10 carries a flrststationary terminal 15 which is.

means of ,the. support memberll which. is fastened; to.

the base 14 by means of bolts or any other desired fastening means which cannot be seen in this figure. Support member 21 is then provided with a bearing 22 upon which the movable contact assembly is pivotally mounted,

The movable contact assembly is more particularly supported on the hinge 23 and comprises the insulator 24 which is bolted to the hinge 23 by means of the bolt 25. Hinge 23 can be further adapted to receive an operating handle which is not shown in the drawing. A conducting member 26 and the blade 27 of the movable contact structure is then fastened to the other end of the insulator 24 by means of the bolt 28.

As shown more clearly in Figure 2, the blade 27 is constructed to engage the second terminal 17 by engaging the jaw contact member 29 which is electrically connected to the terminal 17. law contact member 29 preferably has a spring type characteristic to insure a high pressure contact engagement.

' Blade 16 is further provided with an arcing horn retainer means 30 which holds the blade arcing horn 31. In both of Figures 1 and 2, the blade arcing horn 31 is shown to be engaged with the stationary arcing horn 32, the stationary arcing horn 32 being fastened to the second terminal 17, as by bolt means 33.

It is now necessary to provide a current carrying connection from the first terminal 15 to the movable contact structure and more specifically to the current carrying element 26 which is electrically connected to the movable contact blade 27. As previously mentioned, this connecting means previously comprised a flexible conducting member. In accordance with my invention, however, I show in Figures 1 and 3 that this connecting member is now formed by the conducting linkages 34 and 35, each of the links being formed of rigid current carrying material. This conducting linkage 34 and 35 is provided with three link contact members, 36, 37 and 38.

The physical contact arrangement at contact 36, which is identical to that at contact 38, is more specifically shown in Figure 4, which is a partial top view of the conducting linkages of Figure 1. Here the first terminal 15 which comprises a U-shaped channel is fastened to the blades of the connecting link 34.

The contact itself is more specifically seen in Figure where the first terminal is fastened to the connecting link 34 by means of the bolt 39 and the elastic stop nut 40 which compresses the members 15 and 34 into engagement against the action of a biasing spring 41. In order to provide a silver copper contact engagement, silver Washers 42 and 43 are inserted between the members 15 and 34. The spring assembly may then be weather proofed by means of the casing 44. Therefore, the connecting links 34 and 35 are joined together and to the first terminal 15 and current carrying member 36 by means of a highly effective physical contact arrangement in which high contact pressure is afiorded. For ease of manufacture, it is to be clearly noted that the link contact structures at points 36, 37 and 38 of Figures 1 and 3 will each have the exact dimensions and are easily interchangeable.

It is to be noted at this point that although the preceding description as well as the following description is directed to a tilting insulator switch in which three insulators are used, my novel connecting linkage for conducting currents between a fixed terminal and a movable contact structure can be applied to any type of tilting insulator switch. Similarly, although only a single pole unit is herein described, it is readily understood that in the most usual application, having three poles of this type for a three phase system, three units can be gauged together and driven from a mutual shaft.

The operation of the switch shown in Figure 1 is as follows. When it is desired to operate the switch from the closed position of Figure 1 to the open position of Figure 3 and an operating shaft, which can be connected to the hinge member 23, is rotated to thereby pivot the by the force due to gravity or by a latching arrangement which is not shown here.

In the case of three units ganged together to operate in a three phase system, it is clear that a mutual operating lever can be fastened to each hinge such as the hinge 23 of Figure 1 in order to have one operating lever operate all three poles.

In operating from the disengaged position of Figure 3 to the engaged position of Figure 1, the operating lever is once again moved to force the hinge 23 to rotate in a clockwise direction as viewed in Figure 3 thereby straightening out the conducting linkage 34 and 35 and bringing the blade 27 into contact engagement with thejaw contact member 29 to complete the electrical circuit from the first terminal 15, the link contact 36, conducting link 34, link contact 36, the constructing link 35, the link contact 38, the conducting member 26, the blade 27, the jaw contact member 29, and finally to the second terminal 17. Since the insulator is now to the right of a vertical line through the pivot 22, it is clear that the force of gravity will maintain the switch in its engaged position.

In the case of the switch being mounted vertically, a latching means, which could be operable through the operating handle, would be utilized to maintain the switch in its engaged or disengaged position.

In the foregoing, I have described my invention only in connection with preferred embodiments thereof. Many variations and modifications of the principles of my invention within the scope of the description herein are obvious. Accordingly, I prefer to be bound not by the specific disclosure herein but only by the appending claim.

I claim:

In a tilting insulator switch having a terminal, a movable contact, a stationary contact and a base; said terminal and said stationary contact being supported by said base; said movable contact being mounted on an insulator which is pivotally mounted on said base; said insulator being movable on either side of a vertical line through the pivot of said pivotally mounted insulator to move 'said contact to the engaged and disengaged position respectively with respect to said stationary contact; said terminal and said movable contact being electrically connected by a conducting linkage; said conducting linkage being inflexible in a direction perpendicular to the plane defined by the motion of said movable contact; said conducting linkage comprising a first and second current carrying member; a first, second and third pivotal current carrying structure of identical construction, said first pivotal current carrying contact structure electrically and mechanically connecting said first conducting member and said stationary contact, said second pivotal current carrying contact electrically and mechanically connecting said first and second current carrying members; said third pivotal current carrying contact electrically and mechanically connecting said second current carrying member and said movable contact.

References Cited in the file of this patent UNITED STATES PATENTS 1,935,597 Koppitz Nov. 14, 1933 2,140,907 Froland Dec. 20, 1938 2,211,161 Ramsey Aug. 13, 1940 

